1. Field of the Invention
The present invention relates to an optoelectronic device, in particular to a laser device for optical communication.
2. Description of Related Art
The internet provides a platform for exchanging information. Since the amount of transmitted information like video or audio signal is gradually increased on the internet, the maximum transmission bandwidth of a traditional cable will not be enough in the future. That makes optical fiber replaces the traditional cable to provide larger bandwidth for user.
In order to further increase the amount of transmitted information of the optical fiber, wavelength division multiplex (WDM) technology which can transmit information by several light beams with different wavelengths in an optical fiber is applied to increase the amount of transmitted information.
Conventional triple-wavelength bidirectional WDM optical transmission system has a transmitter optical subassembly (TOSA) and a receiver optical subassembly (ROSA) corresponding to the TOSA. The TOSA has two laser devices and one detecting device mounted together. Each of the laser devices has a laser chip mounted in a TO-CAN package. The detecting device has a detecting chip mounted in a TO-CAN package.
However, the three TO-CAN packages make the TOSA have bigger size, more complicated structure and higher manufacturing cost, thus limit the popularization of the optical communication. Therefore, it becomes a major issue for manufacturer to provide a TOSA with simplified structure and lower manufacturing cost.